Xfn7eH - Online C++0x Compiler & Debugging Tool

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n;
	cin >> n;
	vector<pair<int, int>> vec;
	for(int i = 0; i < n; i++){
		int a, b;
		cin >> a >> b;
		vec.push_back({a, 1});
		vec.push_back({b, -1});
	}
	sort(vec.begin(), vec.end());
	for(int i = 0; i < vec.size(); i++){
		cout << vec[i].first << " " << vec[i].second << endl;
	}
	int ans = 0;
	int sum = 0;
	for(int i = 0; i < vec.size(); i++){
		sum += vec[i].second;
		ans = max(sum, ans);
	}
	cout << ans << endl;
}